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L0301P88 - Stress and Illness
Concept of Stress *elusive *3 approaches to studying stress **stress as an external stimulus **stress as a transaction between the external event and the individual’s reaction **stress as an internal physiological reaction   Stress as an External Stimulus *is any outside force or event that has an effect on our body or mind *effects can be physical or psychological *results from various events/demands *different events stress different people   Typical events: *work pressures *interpersonal conflict *financial pressure *family problems *marriage *divorce *moving house *changing job *deaths *major events *public speaking *children Holmes and Rahe Life Events Theory *study that tried to measure the effect of various external events on one’s health *developed the social readjustment rating scale: >200 per year = increase risk of reporting poor health Limitations: *age dependent *some events may be stressful for one person and not another, e.g. divorce *memory biases - recent = more stressful Stress as a Transaction *psychological model considers not only the nature of the stress, but the nature of the person who experiences the event Appraisal and Stress Response Primary Appraisal *how the subject appraises the event (harm, threat, challenge, benign) Secondary Appraisal *how the subject appraises their own resources and ability to cope *how the person’s emotional response influences their appraisal *e.g. a loss event causes sadness, a threat event causes anxiety *stress occurs when: resources < demands Factors Influencing Appraisal *timing **how soon; is it at an expected time in life *predictability of the event **unpredictable = more stress **e.g. course of an illness *perceived control *amount of life change required **e.g. having a baby *other: mental state, anxiety, previous events   Stress as a Internal Physiological Reaction *how the body responds *once a stress is perceived by the central nervous system: **array of physiological events occur that prepare the body to handle stress **mainly involves the autonomic nervous system and the neuro-endocrine system   Autonomic Nervous System (ANS) *is part of the peripheral nervous system, *acts to control many unconscious bodily function, such as **heart rate, digestion,respiration rate, salivation *classically divided into two subsystems: **parasympathetic nervous system (PNS) **sympathetic nervous system (SNS) *act in harmony to control functions **SNS is like the accelerator **PNS is like the brake SNS - Acute Response to Stress *promotes a "fight or flight" response *corresponds with arousal, energy generation, and inhibition of digestion *meant to be a short-term response *but in the current society, the response is often lengthy and has adverse effects Physiological Changes *vasoconstriction: **gastro-intestinal (GI) tract ***inhibits peristalsis **skin *vasodilation: **skeletal muscles, lungs **coronary vessels of the heart *increases heart rate and contractility of cardiac cells **providing a mechanism for the enhanced blood flow to skeletal muscles *dilation of: **bronchioles of the lung ***greater alveolar oxygen exchange **pupils and relaxes the lens ***more light to enter the eye PNS *promotes a "rest and digest" response **calming of the emotional responses **return to regular function **enhances digestion Physiological Changes *dilates blood vessels leading to the GI tract **important following the consumption of food = greater metabolic demands placed on the body by the gut *constriction of: **bronchiolar diameter when the need for oxygen has diminished **pupil *stimulates salivary gland secretion, and accelerates peristalsis Cox & Mackay Model of Stress Impact of Stress Organisational Effects *burnout, low morale, low performance, poor working relationships, absenteeism, high turnover, job dissatisfaction, high use of health facilities, accidents Behavioural Effects *drug use, alcohol, smoking, overeating, appetite, impulsive/aggressive outbursts, accident proneness, restlessness, blaming others, withdrawal, isolation Cognitive Effects *concentration, task performances, defensiveness, mental blocks, sleepiness Emotional Effects *anxiety, anger, boredom, depression, fatigue, frustration, irritability, worry moodiness, tension, nervousness, self-hate Physical Effects *imbalance including blood glucose, heart rate, blood pressure, breathing *numbness, tingling, physical pain, fatigue, medically unexplained symptoms *result: damage to organs, chronic disease Types of Stress Acute Stress Cataclysmic *big events initially cause panic,anxiety, withdrawal, anger, disorientation, sleep disturbance, eating problems *can increase risk of mental illness including post-traumatic stress disorder **flashbacks and reliving **avoidance **hyperarousal - jumpy   Routine *common events that cause stress *Yerkes-Dodson Law - there is an optimum level of arousal necessary to maintain attention and memory, too much and you deteriorate, too little and you don’t perform *e.g. exams, anniversary of a family member’s death Chronic Stress *work place is the commonest site to study chronic stress *leads to burn out *work stress may be due to demand, controllability, predictability, ambiguity Stress and Disease Direct Route *direct physiological changes in the endocrine and immune system Indirect Route *via responses to stress such as smoking, drinking and eating *via the manner in which people respond to stress (via personality) *via increase use of health resources Stress and Heart Disease *direct - stress changes heart rate and vessel constriction via the SNS, which in theory can alter rate of vessel damage *indirect - stress is associated with hypertension and smoking Stress and Bowel Disease *direct - stress has been associated to varying degrees with most bowel diseases **strong association with Irritable Bowel Syndrome *less so with inflammatory bowel disease (Ulcerative Colitis, Crohn’s Disease) Stress and Multiple Sclerosis *acute stress has a small impact on acute relapses and vice versa *chronic stress has no effect Factors Affecting Stress Social Support *definition - assistance received from others *types **emotional e.g. empathy, care, concern **esteem e.g. positive encouragement **instrumental e.g. direct assistance – cash, mow lawn **information e.g. advice, suggestions **network e.g. linking and connection *effects **reduced mortality **low social support - isolation and loneliness correlates with increased risk of disease *how it works **direct effect theory ***healthier lifestyle ***decreased physiological reactivity ***possible immunity and endocrine effects **buffering theory ***changes in one’s appraisal and coping responses Coping *what a person does to reduce the impact of a perceived stressor *decrease negative emotions *alter the stressor directly *e.g. relationship break-up *classification of coping strategies **adaptive **maladaptive ***alcohol to excess, violence, drug taking, complete denial *individual coping with chronic conditions varies: **cognitive responses ***helplessness: emphasis on negative aspects, increased disability ***acceptance: decreases negative cognitions ***perceived benefit: adds optimistic meaning to the condition **controllability **efficacy/self-efficacy **optimism Styles *problem focussed **planning, confronting, seeking information *emotion focussed **support seeking, venting, praying, reframing *attentional **vigilant monitoring *avoidant **distraction, daydreaming Personality Negative *hostility - unhealthy behaviour, less accepting of support, increased physiological responses *neuroticism - anxious thoughts, feelings and behaviours, higher self-reported illnesses but no objective increase in physical illnesses Positive *optimism - associated with less stress *hardiness - in high stress environments, more hardiness = less illness   Locus of Control *belief of where responsibly/control lies for the forces that affect one’s life *can be internal or external